System and method for facilitating a cardiac rhythm disorder diagnosis with the aid of a digital computer

ABSTRACT

A system for facilitating a cardiac rhythm disorder diagnosis with the aid of a digital computer is provided. A download station retrieves cutaneous action potentials of a patient by an ECG monitoring and recording device as ECG data. An R-R interval plot of the ECG data includes R-R intervals plotted along an x-axis of the plot and heart rates associated with the R-R intervals plotted along a y-axis of the plot. The R-R intervals are calculated as a difference between recording times of successive pairs of R-wave peaks and each heart rate is associated with each time difference. Runs of the R-R intervals in the plot are identified and each run represents a cardiac event. Cardiac rhythm measurements are automatically calculated and occurrences of different types of the cardiac events are tracked. One or more of the cardiac events and the cardiac rhythm measurements are reported.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional patent application is continuation of U.S. patentapplication Ser. No. 16/537,408, filed Aug. 9, 2019, pending; which is acontinuation-in-part of U.S. Pat. No. 10,736,532, issued Aug. 11, 2020;which is a continuation of U.S. Pat. No. 10,045,709, issued Aug. 14,2018; which is a continuation of U.S. Pat. No. 9,408,551, issued Aug. 9,2016; which is a continuation-in-part of U.S. Pat. No. 9,345,414, issuedMay 24, 2016; which is a continuation-in-part of U.S. Pat. No.9,408,545, issued Aug. 9, 2016; which is a continuation-in-part of U.S.Pat. No. 9,700,227, issued Jul. 11, 2017; which is acontinuation-in-part of U.S. Pat. No. 9,730,593, issued Aug. 15, 2017,and further claims priority under 35 U.S.C. § 119(e) to U.S. ProvisionalPatent Application, Ser. No. 62/132,497, filed Mar. 12, 2015, and U.S.Provisional Patent Application, Ser. No. 61/882,403, filed Sep. 25,2013, the disclosures of which are incorporated by reference.

FIELD

This application relates in general to electrocardiographic monitoringand, in particular, to a method for facilitating diagnosis of cardiacrhythm disorders with the aid of a digital computer.

BACKGROUND

An electrocardiogram (ECG) allows physicians to diagnose cardiacfunction by visually tracing the cutaneous electrical signals (actionpotentials) that are generated by the propagation of the transmembraneionic currents that trigger the depolarization of cardiac fibers. An ECGtrace contains alphabetically-labeled waveform deflections thatrepresent distinct features within the cyclic cardiac activationsequence. The P-wave represents atrial depolarization, which causesatrial contraction. The QRS-complex represents ventriculardepolarization. The T-wave represents ventricular repolarization.

The R-wave is often used as an abbreviation for the QRS-complex. An R-Rinterval spans the period between successive R-waves and, in a normalheart, is 600 milliseconds (ms) to one second long, which respectivelycorrespond to 100 to 60 beats per minute (bpm). The R-wave is thelargest waveform generated during normal conduction and represents thecardiac electrical stimuli passing through the ventricular walls. R-Rintervals provide information that allows a physician to understand at aglance the context of cardiac rhythms both before and after a suspectedrhythm abnormality and can be of confirmational and collaborative valuein cardiac arrhythmia diagnosis and treatment.

Conventionally, the potential of R-R interval context has not been fullyrealized, partly due to the difficulty of presentation in a concise andeffective manner to physicians. For instance, routine ECGs are typicallydisplayed at an effective paper speed of 25 millimeters (mm) per second.A lower speed is not recommended because ECG graph resolution degradesat lower speeds and diagnostically-relevant features may be lost.Conversely, a half-hour ECG recording, progressing at 25 mm/s, resultsin 45 meters of ECG waveforms that, in printed form, is cumbersome and,in electronic display form, will require significant back and forthtoggling between pages of waveforms, as well as presenting voluminousdata transfer and data storage concerns. As a result, ECGs are less thanideal tools for diagnosing cardiac arrhythmia patterns that only becomeapparent over an extended time frame, such as 30 minutes or longer.

R-R intervals have also been visualized in Poincaré plots, which graphRR(n) on the x-axis and RR(n+1) on the y-axis. However, a Poincaré plotfails to preserve the correlation between an R-R interval and the R-Rinterval's time of occurrence and the linearity of time and associatedcontextual information, before and after a specific cardiac rhythm, arelost. In addition, significant changes in heart rate, particularlyspikes in heart rate, such as due to sinus rhythm transitions to atrialflutter or atrial fibrillation, may be masked or distorted in a Poincaréplot if the change occurs over non-successive heartbeats, rather thanover two adjacent heartbeats, which undermines reliance on Poincaréplots as dependable cardiac arrhythmia diagnostic tools. Further,Poincaré plots cannot provide context and immediate temporal referenceto the actual ECG, regardless of paper speed. Events both prior to andafter a specific ECG rhythm can provide key clinical informationdisclosed in the R-R interval plot that may change patient managementabove and beyond the specific rhythm being diagnosed.

Cardiac patients can require full time monitoring, such as via a dermalor implantable cardiac device. Currently, a single cardiac device canrecord data over a period of 7 to 14 days, or more, before charging ordata offload is required. Once offloaded, the cardiac data can beprocessed for providing to a physician or other medical professional fordiagnosis of the patient. However, the large amounts of data collectedover time are often difficult or not possible to display using currentsoftware to provide the diagnosing medical professional with the“complete picture” of the cardiac environment of the patient, includingabnormal heart beats and rhythm patterns. Further, viewing the “completepicture” allows other medical professionals to easily spot and removenoise from the cardiac data.

Therefore, a need remains for presenting R-R interval data to physiciansto reveal temporally-related patterns as an aid to rhythm abnormalitydiagnosis. Preferably, the presentation allows a physician or othermedical professional to visualize an entire data set, recorded over aperiod of time, to obtain a complete picture of a patient's cardiacsituation, to diagnose a patient or remove noise.

SUMMARY

R-R interval data is presented to physicians in a format that includesviews of relevant near field and far field ECG data, which togetherprovide contextual information that improves diagnostic accuracy. Thenear field (or short duration) ECG data view provides a “pinpoint”classical view of an ECG at traditional recording speed in a manner thatis known to and widely embraced by physicians. The near field ECG datais coupled to a far field (or medium duration) ECG data view thatprovides an “intermediate” lower resolution, pre- and post-eventcontextual view.

Both near field and far field ECG data views are temporally keyed to anextended duration R-R interval data view. In one embodiment, the R-Rinterval data view is scaled non-linearly to maximize the visualdifferentiation for frequently-occurring heart rate ranges, such that asingle glance allows the physician to make a diagnosis. All three viewsare presented simultaneously, thereby allowing an interpreting physicianto diagnose rhythm and the pre- and post-contextual events leading up toa cardiac rhythm of interest.

The durations of the classical “pinpoint” view, the pre- and post-event“intermediate” view, and the R-R interval plot are flexible andadjustable. In one embodiment, a temporal point of reference isidentified in the R-R interval plot and the ECG data that is temporallyassociated with the point of reference is displayed in the near fieldand far field ECG data views. In a further embodiment, diagnosticallyrelevant cardiac events can be identified as the temporal point ofreference. For clarity, the temporal point of reference will generallybe placed in the center of the R-R interval data to allow pre- andpost-event heart rhythm and ECG waveform data to present in the correctcontext. Thus, the pinpoint “snapshot” and intermediate views of ECGdata with the extended term R-R interval data allow a physician tocomparatively view heart rate context and patterns of behavior prior toand after a clinically meaningful arrhythmia, patient concern or otherindicia, thereby enhancing diagnostic specificity of cardiac rhythmdisorders and providing physiological context to improve diagnosticability.

Further, providing a medical professional with a complete view of apatient's cardiac data collected over time, allows a professional toeasily identify noise, as well as abnormal heart beats and rhythmpatterns, which may be indicative of a cardiac condition. Additionally,snippets of the data can be collected from the complete picture, such asthose representing the abnormal rhythm patterns for providing adifferent medial professional with a summary view of the patient'scardiac environment.

One embodiment provides a system and method for facilitating a cardiacrhythm disorder diagnosis with the aid of a digital computer. A downloadstation retrieves cutaneous action potentials of a patient recorded overtime by an ECG device as ECG data. An R-R interval plot of the ECG dataincludes R-R intervals plotted along an x-axis of the plot and heartrates associated with the R-R intervals plotted along a y-axis of theplot. The R-R intervals are calculated as a difference between recordingtimes of successive pairs of R-wave peaks. Each heart rate is associatedwith each time difference. One or more portions of the R-R intervals areidentified in the plot. Each portion of the R-R intervals includes acardiac event. Report strips are generated and each includes one portionof the R-R intervals and a portion of the ECG data spanning a shorterduration than that portion of the R-R intervals.

The foregoing aspects enhance the presentation of diagnosticallyrelevant R-R interval data, reduce time and effort needed to gatherrelevant information by a clinician and provide the clinician with aconcise and effective diagnostic tool, which is critical to accuratearrhythmia and cardiac rhythm disorder diagnoses.

A further embodiment provides a system for facilitating a cardiac rhythmdisorder diagnosis with the aid of a digital computer. A downloadstation is adapted to retrieve cutaneous action potentials of a patientrecorded over a set period of time by an ECG monitoring and recordingdevice as ECG data. An R-R interval plot of the ECG data includes R-Rintervals plotted along an x-axis of the plot and heart rates associatedwith the R-R intervals plotted along a y-axis of the plot. The R-Rintervals are calculated as a difference between recording times ofsuccessive pairs of R-wave peak and each heart rate is associated witheach time difference. One or more portions of the R-R intervals areidentified in the plot as a run with a cardiac event by marking a startand an end of each portion of the R-R intervals. One or more reportstrips are generated and each report strip includes one of the runs anda portion of the ECG data spanning a shorter duration than the run. Thereport strips are collected for inclusion in a cardiac report.

A still further embodiment provides a system for facilitating a cardiacrhythm disorder diagnosis with the aid of a digital computer. A downloadstation retrieves cutaneous action potentials of a patient by an ECGmonitoring and recording device as ECG data. An R-R interval plot of theECG data includes R-R intervals plotted along an x-axis of the plot andheart rates associated with the R-R intervals plotted along a y-axis ofthe plot. The R-R intervals are calculated as a difference betweenrecording times of successive pairs of R-wave peaks and each heart rateis associated with each time difference. Runs of the R-R intervals inthe plot are identified and each run represents a cardiac event. Cardiacrhythm measurements are automatically calculated and occurrences ofdifferent types of the cardiac events are tracked. One or more of thecardiac events and the cardiac rhythm measurements are reported.

Custom software packages have been used to identify diagnosticallyrelevant cardiac events from the electrocardiography data, but usuallyrequire a cardiologist's diagnosis and verification. In contrast, whenpresented with a machine-identified event, the foregoing approach aidsthe cardiologist's diagnostic job by facilitating presentation ofECG-based background information prior to and after the identifiedevent.

Still other embodiments will become readily apparent to those skilled inthe art from the following detailed description, wherein are describedembodiments by way of illustrating the best mode contemplated. As willbe realized, other and different embodiments are possible and theembodiments' several details are capable of modifications in variousobvious respects, including time and clustering of events, all withoutdeparting from their spirit and the scope. Accordingly, the drawings anddetailed description are to be regarded as illustrative in nature andnot as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph showing, by way of example, a single ECG waveform.

FIG. 2 is a graph showing, by way of example, a prior art Poincaré R-Rinterval plot.

FIG. 3 is a flow diagram showing a method for facilitating diagnosis ofcardiac rhythm disorders with the aid of a digital computer inaccordance with one embodiment.

FIG. 4 is a flow diagram showing a routine for constructing anddisplaying a diagnostic composite plot for use in the method of FIG. 3.

FIG. 5 is a flow diagram showing a routine for constructing anextended-duration R-R interval plot for use in the routine of FIG. 4.

FIG. 6 is a diagram showing, by way of example, a diagnostic compositeplot generated by the method of FIG. 3.

FIG. 7 is a diagram showing, by way of example, a diagnostic compositeplot for facilitating the diagnosis of sinus rhythm (SR) transitioninginto atrial fibrillation (AF).

FIG. 8 is a diagram showing, by way of example, a diagnostic compositeplot for facilitating the diagnosis of 3:1 atrial flutter (AFL)transitioning into SR.

FIG. 9 is a diagram showing, by way of example, a diagnostic compositeplot for facilitating the diagnosis of atrial trigeminy.

FIG. 10 is a diagram showing, by way of example, a diagnostic compositeplot for facilitating the diagnosis of maximum heart rate in an episodeof AF during exercise.

FIG. 11 is a diagram showing, by way of example, a diagnostic compositeplot for facilitating the diagnosis of SR transitioning into AFLtransitioning into AF.

FIG. 12 is a diagram showing, by way of example, a diagnostic compositeplot for facilitating the diagnosis of sinus tachycardia andpalpitations that occurred during exercise accompanied by a jump inheart rate.

FIG. 13 is a diagram showing, by way of example, a diagnostic compositeplot for facilitating the diagnosis of bradycardia.

FIG. 14 is a block diagram showing a system for facilitating diagnosisof cardiac rhythm disorders with the aid of a digital computer inaccordance with one embodiment.

FIG. 15 is a screenshot of an interactive user interface for displayingan overview of an R-R plot.

FIG. 16 is a diagram showing, by way of example, data zooming.

FIG. 17 is a diagram showing, by way of example, an interactive userinterface for generating a run of data.

FIG. 18 is a diagram showing, by way of example, an interactive userinterface for displaying a classified run of data.

FIG. 19 is a diagram showing, by way of example, an interactive userinterface generating a further run of data points.

FIG. 20 is a diagram showing, by way of example, an interactive userinterface for assigning a classification to the further run of FIG. 19.

FIG. 21 is a screenshot of an interactive user interface for displayingan overview ECG trace plot.

FIG. 22 is a diagram showing, by way of example, data zooming of the ECGtrace plot of FIG. 21.

FIG. 23 is a diagram showing, by way of example, an interactive userinterface for displaying a selected data strip.

FIG. 24 is a diagram showing, by way of example, an interactive userinterface for generating a run of ECG trace data.

FIG. 25 is a diagram showing, by way of example, an interactive userinterface for saving a run of ECG trace data.

FIG. 26 is a diagram of an interactive user interface for conducting asearch for cardiac events.

FIG. 27 is a diagram of an interactive user interface for displayingdata for inclusion in a patient report.

FIG. 28 is a view of a patient report.

FIGS. 29-31 are diagrams showing, the report of FIG. 28 in furtherdetail.

DETAILED DESCRIPTION

A normal healthy cardiac cycle repeats through an expected sequence ofevents that can be visually traced through an ECG. Each cycle startswith cardiac depolarization originating high in the right atrium in thesinoatrial (SA) node before spreading leftward towards the left atriumand inferiorly towards the atrioventricular (AV) node. After a delay inthe AV node, the depolarization impulse transits the Bundle of His andmoves into the right and left bundle branches and Purkinje fibers toactivate the right and left ventricles.

When a rhythm disorder is suspected, diagnostically-relevant arrhythmicevents in the cardiac cycle can often be identified and evaluated withthe assistance of an ECG and R-R interval tachography, such as Poincaréplots. Routine ECG evaluation is primarily focused identifying changesto expected ECG waveform shapes. FIG. 1 is a graph showing, by way ofexample, a single ECG waveform 10. The x-axis represents approximatetime in units of tenths of a second and the y-axis representsapproximate cutaneous electrical signal strength in units of millivolts.By long-standing convention, ECGs are typically printed or displayed atan effective paper speed of 25 millimeters (mm) per second. Although inpractice an ECG may be provided to a physician in traditionalpaper-printed form, in “virtual” electronic display form, or both, theterm “effective paper speed” is nevertheless still widely applied as ametric to normalize the recorded ECG signal to a standardized grid of 1mm squares (omitted for the sake of clarity in FIG. 1), whereby each 1mm horizontal box in the grid corresponds to 0.04 s (40 ms) of recordedtime. Other effective paper speeds, grid sizes and units of display arepossible.

A full ECG consists of a stream of alphabetically-labeled waveforms 10that collectively cover cardiac performance over a period ofobservation. For a healthy patient, within each ECG waveform 10, theP-wave 11 will normally have a smooth, normally upward, positivewaveform that indicates atrial depolarization. The QRS complex 17 willusually follow, often with a downward deflection of a Q-wave 12,followed by a larger upward deflection of an R-wave 13, and beterminated with a downward waveform of the S-wave 14, which arecollectively representative of ventricular depolarization. The T-wave 15will normally be a modest upward waveform, representative of ventricularrepolarization, while the U-wave 16, which is often not directlyobservable, will indicate the recovery period of the Purkinje conductionfibers.

Rhythm disorders often manifest through R-R interval variability and thepatterns formed by R-R intervals over an extended time period areimportant tools in the diagnosis of cardiac rhythm abnormalities. Forexample, atrial fibrillation (AF) is the chaotic firing of the atriathat leads to an erratic activation of the ventricles. AF is initiallydiagnosed by an absence of organized P-waves 11 and confirmed by erraticventricular rates that manifest in an ECG R-R interval plot as acloud-like pattern of irregular R-R intervals due to an abnormalconduction of impulses to the ventricles. There is a Gaussian-likedistribution to these R-R intervals during AF. Similarly, atrial flutter(AFL) is an abnormal heart rhythm in which cardiac impulses travel alongpathways within the right atrium in an organized circular motion,causing the atria to beat faster than and out of sync with theventricles. During AFL, the heart beats quickly, yet with a regularpattern. Although AFL presents in an electrogram (e-gram) as a“sawtooth” pattern, AFL can be confirmed in an ECG by characteristic R-Rinterval patterns that usually manifest as 2:1 atrioventricular (AV)conduction or 4:1 atrioventricular conduction. On occasion, theconduction through the AV node is variable and not fixed.

Conventionally, R-R intervals have been visualized using Poincaré plots.FIG. 2 is a graph showing, by way of example, a prior art Poincaré R-Rinterval plot 18. The x-axis represents the duration of R-R interval nin units of milliseconds (ms). The y-axis represents the duration of R-Rinterval n+1 also in units of ms. Ordinarily, the x- and y-axes use thesame units, so as to form a trend line 19 along the 45-degree angle.When an R-R interval is equal to the successive R-R interval, as oftenoccurs when heart rhythm is regular, the dot representing the twointervals falls onto the 45-degree trend line 19. Conversely, when anR-R interval has changed since the preceding R-R interval, the dotrepresenting the two intervals falls off the 45-degree trend line 19and, as the difference between successive R-R intervals increases, thedots fall further away from the trend line 19.

The number of dots deviating from the trend line 19 in a Poincaré plotcan indicate the frequency of occurrence of irregular heartbeats whencompared to the number of dots on the trend line 19. The distance of thedots to the trend line 19 can approximate the extent of heart ratechange from one heartbeat to the next. However, as heart rate change islimited to only successively-occurring heartbeats, the linearity of timeand associated contextual information over an extended time frame arelost. In addition, significant changes in heart rate, particularlyspikes in heart rate, such as due to sinus rhythm transitions to atrialflutter, may be masked, distorted or even omitted in a Poincaré plot ifthe change occurs over non-successive heartbeats. In summary, a Poincaréplot is more useful as a mathematical tool than a physiological one, andtherefore a Poincaré plot cannot truly represent what the heart is doingserially over time with respect to changes in the heart's normal andabnormal physiology.

Despite the limitations of Poincaré plots and related forms of R-Rinterval tachography, R-R interval data when presented in a formatduplicating temporal physiological events remains a key tool thatphysicians can rely upon to identify temporally-related cardiacdysrhythmic patterns. Interpretation of R-R interval data can beassisted by including multiple temporal points of reference and a plotof R-R interval data that comparatively depicts heart rate variabilityin concert with R-R interval data. FIG. 3 is a flow diagram showing amethod 20 for facilitating diagnosis of cardiac rhythm disorders withthe aid of a digital computer in accordance with one embodiment. Themethod 20 can be implemented in software and execution of the softwarecan be performed on a computer, such as further described infra withreference to FIG. 14, as a series of process or method modules or steps.

As a precursor step, the cutaneous action potentials of a patient aremonitored and recorded as ECG data over a set time period (step 21),which can be over a short term or extended time frame. ECG recordation,as well as physiological monitoring, can be provided through variouskinds of ECG-capable monitoring ensembles, including a standardized12-lead ECG setup, such as used for clinical ECG monitoring, a portableHolter-type ECG recorder for traditional ambulatory ECG monitoring, or awearable ambulatory ECG monitor, such as a flexible extended wearelectrode patch and a removable reusable (or single use) monitorrecorder, such as described in commonly-assigned U.S. Pat. No.9,345,414, issued May 24, 2016, the disclosure of which is incorporatedby reference, the latter of which includes an electrode patch andmonitor recorder that are synergistically optimized to captureelectrical signals from the propagation of low amplitude, relatively lowfrequency content cardiac action potentials, particularly the P-waves,generated during atrial activation. Still other forms of ECG monitoringassembles are possible.

Upon completion of the monitoring period, the ECG and any physiologicaldata are downloaded or retrieved into a digital computer, as furtherdescribed infra with reference to FIG. 14, with, for instance, theassistance of a download station or similar device, or via wirelessconnection, if so equipped, and a vector of the downloaded or retrievedECG data is obtained (step 22). In one embodiment, the vector of ECGdata represents a 40-minute (or other duration) time span that is usedin constructing the plot of R-R interval data, although other pre-eventand post-event time spans are possible. Optionally, apotentially-actionable cardiac event within the vector of ECG data canbe identified and the ECG data during, prior to and after the event isselected (step 23). The event could be identified with the assistance ofa software package, such as Holter LX Analysis Software, licensed byNorthEast Monitoring, Inc., Maynard, Mass.; IntelliSpace CardiovascularImage and Information management system, licensed Koninklijke PhilipsN.V., Amsterdam, Netherlands; MoMe System, licensed by InfoBionic,Lowell, Mass.; Pyramis ECG Management, licensed by Mortara InstrumentInc., Milwaukee, Wis.; ICS Clinical Suite, licensed by SpacelabsHealthcare Inc., Snoqualmie, Wash.; or a customized software package.Alternatively, the potentially-actionable cardiac event could beidentified by a physician or technician during review of the ECG data.

To improve diagnosis of heart rate variability, a diagnostic compositeplot is constructed that includes one or more temporal points ofreference into the ECG data, which provide important diagnostic context,and a plot of R-R interval data is constructed based on the vector ofECG data (step 24), as further described infra with reference to FIG. 4.Briefly, both near field and far field contextual views of the ECG dataare constructed and displayed. Both views are temporally keyed to anextended duration R-R interval data view that, in one embodiment, isscaled non-linearly to maximize the visual differentiation forfrequently-occurring heart rate ranges, such that a single glance allowsthe physician to make a diagnosis. All three views are presentedsimultaneously, thereby allowing the interpreting physician to diagnoserhythm and the pre- and post-contextual events leading up to a cardiacrhythm of interest.

In a further embodiment, findings made through interpretation of heartrate variability patterns in the diagnostic composite plot can beanalyzed to form a diagnosis of a cardiac rhythm disorder (step 25),such as the cardiac rhythm disorders listed, by way of example, inTable 1. For instance, the heart rate variability patterns in thediagnostic composite plot could be provided to a system thatprogrammatically detects AF by virtue of looking for the classicGaussian-type distribution on the “cloud” of heart rate variabilityformed in the plot of R-R interval data, which can be corroborated bythe accompanying contextual ECG data. Finally, therapy to addressdiagnosed disorder findings can optionally be programmed into a cardiacrhythm therapy delivery device (step 26), such as an implantable medicaldevice (IMD) (not shown), including a pacemaker, implantablecardioverter defibrillator (ICD), or similar devices.

TABLE 1 Cardiac Rhythm Disorders Normal sinus rhythm Sinus BradycardiaSinus Tachycardia Premature atrial and ventricular beats Ectopic atrialtachycardia Atrial fibrillation Atrial flutter Atrial or ventricularbigeminy, trigeminy or quadrigeminy Sinus Bradycardia Fusion beatsInterpolated ventricular premature beats Intraventricular conductiondelay Junctional rhythm AV Nodal re-entrant tachycardia AV re-entranttachycardia Wolff-Parkinson-White Syndrome and Pre-excitationVentricular tachycardia Accelerated idioventricular rhythm AV Wenckebachblock AV Type II block Sinoatrial block

A diagnostic composite plot is constructed and displayed to helpphysicians identify and diagnose temporally-related cardiac dysrhythmicpatterns. The diagnostic composite plot includes ECG traces from two ormore temporal points of reference and a plot of R-R interval data,although other configurations of ECG data plots when combined with theR-R interval plot will also provide critical information. FIG. 4 is aflow diagram showing a routine 30 for constructing and displaying adiagnostic composite plot for use in the method 20 of FIG. 3. Specificexamples of diagnostic composite plots are discussed in detail infrawith reference to FIGS. 7-13.

In the diagnostic composite plot, R-R interval data is presented tophysicians in a format that includes views of relevant near field andfar field ECG data, which together provide contextual information thatimproves diagnostic accuracy. In a further embodiment, other views ofECG data can be provided in addition to or in lieu of the near field andfar field ECG data views. The near field (or short duration) ECG dataprovides a “pinpoint” classical view of an ECG at traditional recordingspeed in a manner that is known to and widely embraced by physicians.The near field ECG data is coupled to a far field (or medium duration)ECG data view that provides an “intermediate” lower resolution, pre- andpost-event contextual view. Thus, the extended-duration R-R intervalplot is first constructed (step 31), as further described infra withreference to FIG. 5.

Optionally, noise can be filtered from the R-R interval plot (step 32),which is then displayed (step 33). Noise filtering can include low-passor high-pass filtering or other forms of signal processing, includingautomatic gain control, such as described in commonly-assigned U.S. Pat.No. 9,345,414, cited supra. Rhythm disorders have different weightingsdepending upon the context with which they occur. In the diagnosticcomposite plot, the R-R interval data view and the multiple views of theECG data provide that necessary context. Effectively, the short andmedium duration ECG data that accompanies the extended-duration R-Rinterval plot represents the ECG data “zoomed” in around a temporalpoint of reference identified in the center (or other location) of theR-R interval plot, thereby providing a visual context to the physicianthat allows temporal assessment of cardiac rhythm changes in variouscomplementary views of the heart's behavior. The durations of theclassical “pinpoint” view, the pre- and post-event “intermediate” view,and the R-R interval plot are flexible and adjustable. In oneembodiment, the diagnostic composite plot displays R-R interval dataover a forty-minute duration and ECG data over short and mediumdurations (steps 34 and 35), such as four-second and 24-second durationsthat provide two- and 12-second segments of the ECG data before andafter the R-R interval plot's temporal point of reference, which isgenerally in the center of the R-R interval plot, although otherlocations in the R-R interval plot could be identified as the temporalpoint of reference. The pinpoint “snapshot” and intermediate views ofECG data with the extended term R-R interval data comparatively depictsheart rate context and patterns of behavior prior to and after aclinically meaningful arrhythmia or patient concern, thereby enhancingdiagnostic specificity of cardiac rhythm disorders and providingphysiological context to improve diagnostic ability. In a furtherembodiment, diagnostically relevant cardiac events can be identified andthe R-R interval plot can be constructed with a cardiac event centeredin the middle (or other location) of the plot, which thereby allows pre-and post-event heart rhythm data to be contextually “framed” through thepinpoint and intermediate ECG data views. Other durations, intervals andpresentations of ECG data are possible.

The extended-duration R-R interval plot presents beat-to-beat heart ratevariability in a format that is intuitive and contextual, yet condensed.The format of the R-R interval plot is selected to optimizevisualization of cardiac events in a compressed, yet understandablefield of view that allows for compact presentation of the data akin to acardiologist's understanding of clinical events. FIG. 5 is a flowdiagram showing a routine 40 for constructing an extended-duration R-Rinterval plot for use in the routine 30 of FIG. 4. The duration of theR-R interval plot can vary from less than one minute to the entireduration of the recording. Thus, a plurality of R-wave peaks is firstselected out of the vector of ECG data (step 41) appropriate to theduration of the R-R interval plot to be constructed. For successivepairs of the R-wave peaks (steps 42-43), the difference between therecording times of the R-peaks is calculated (step 43). Each recordingtime difference represents the length of one heartbeat. The heart rateassociated with the recording time difference is determined by taking aninverse of the recording time difference and normalizing the inverse tobeats per minute (step 44). Taking the inverse of the recording timedifference yields a heart rate expressed in beats per second, which canbe adjusted by a factor of 60 to provide a heart rate expressed in bpm.Calculation of the differences between the recording times and theassociated heart rate continues for all of the remaining pairs of theR-wave peaks (step 44).

The pairings of R-R intervals and associated heart rates are formed intoa two-dimensional plot. R-R intervals are plotted along the x-axis andassociated heart rates are plotted along the y-axis. The range and scaleof the y-axis (heart rate) can be adjusted according to the range andfrequency of normal or patient-specific heart rates, so as to increasethe visual distinctions between the heart rates that correspond todifferent R-R intervals. In one embodiment, the y-axis of the R-Rinterval plot has a range of 20 to 300 beats per minute and R-Rintervals corresponding to heart rates falling extremely outside of thisrange are excluded to allow easy visualization of 99+% of the heart ratepossibilities.

In a further embodiment, they-axis has a non-linear scale that iscalculated as a function of the x-axis (R-R interval), such that:

$y = \left( \frac{x - {\min \mspace{14mu} {bpm}}}{{\max \mspace{14mu} {bpm}} - {\min \mspace{14mu} {bpm}}} \right)^{n}$

where x is the time difference, min bpm is the minimum heart rate, maxbpm is the maximum heart rate, and n<1. The non-linear scale of they-axis accentuates the spatial distance between successive heart rateswhen heart rate is low. For example, when n=2, the spatial differencebetween 50 and 60 bpm is 32% larger than the spatial difference between90 bpm and 100 bpm, and 68% larger than the spatial difference between150 bpm and 160 bpm. As a result the overall effect is to accentuate thespatial differences in frequently-occurring ranges of heart rate andde-emphasize the spatial differential in ranges of heart rate where adeviation from norm would have been apparent, thus maximizing thespatial efficiency in data presentation. The goal is to show cardiacevents in a simple, small visual contextual format. Larger scales andlarger formats bely the practical limits of single-page presentationsfor the easy visualization at a glance by the busy physician. The visualdistinctions between the heart rates that correspond to different R-Rintervals stand out, especially when plotted on a non-linear scale.Other y-axis ranges and scales are possible as may be selected bydistinct clinical needs and specific diagnostic requirements.

The diagnostic composite plot includes a single, long range view of R-Rinterval data and a pair of pinpoint ECG data views that together helpto facilitate rhythm disorder diagnosis by placing focused long-termheart rate information alongside short-term and medium-term ECGinformation. Such pairing of ECG and R-R interval data is unique in itsability to inform the physician of events prior to, during and after acardiovascular event. FIG. 6 is a diagram showing, by way of example, adiagnostic composite plot 50 generated by the method 30 of FIG. 3. Notethat the diagnostic composite plot can be tailored to include more thanone view of R-R interval data and as many views of contextual ECG dataas needed. In a further embodiment, a background information plotpresenting an extended far field of related information can be included,such as activity amount, activity intensity, posture, syncope impulsedetection, respiratory rate, blood pressure, oxygen saturation (SpO₂),blood carbon dioxide level (pCO₂), glucose, lung wetness, andtemperature. Other forms of background information are possible. In astill further embodiment, background information can be layered on topof or keyed to the diagnostic composite plot 50, particularly at keypoints of time in the R-R interval data plot, so that the contextprovided by each item of background information can be readily accessedby the reviewing physician.

The diagnostic composite plot 50 includes an ECG plot presenting a nearfield (short duration) view 51, an ECG plot presenting an intermediatefield (medium duration) view 52, and an R-R interval data plotpresenting a far field (extended duration) view 53. The three views 51,52, 53 are juxtaposed alongside one other to allow quick back and forthreferencing of the full context of the heart's normal and abnormalphysiology. Typically, a temporal point of reference, which could be adiagnostically relevant cardiac event, patient concern or other indicia,would be identified and centered on the x-axis in all three views. Theplacement of the temporal point of reference in the middle of all threex-axes enables the ECG data to be temporally keyed to the R-R intervaldata appearing in the center 60 of the R-R interval data view 53, with anear field view 51 of an ECG displayed at normal (paper-based) recordingspeed and a far field view 52 that presents the ECG data occurringbefore and after the center 60. As a result, the near field view 51provides the ECG data corresponding to the R-R interval data at thecenter 60 (or other location) in a format that is familiar to allphysicians, while the intermediate field view 52 enables presentation ofthe broader ECG data context going beyond the borders of the near fieldview 51. In a further embodiment, the center 60 can be slidably adjustedbackwards and forwards in time, with the near field view 51 and the farfield view 52 of the ECG data automatically adjusting accordingly tostay in context with the R-R interval data view 51. In a still furtherembodiment, multiple temporal points of reference can be identified witheach temporal point of reference being optionally accompanied by one ormore dedicated sets of ECG data views.

The collection of plots are conveniently arranged close enough to oneanother to facilitate printing on a single page of standard sized paper(or physical paper substitute, such as a PDF file), although otherlayouts of the plots are possible. The far field view 53 is plotted withtime in the x-axis and heart rate in the y-axis. The R-R intervals arecalculated by measuring the time occurring between successive R-wavepeaks. In one embodiment, the far field view 53 presents R-R intervaldata (expressed as heart rate in bpm) that begins about 20 minutes priorto and ends about 20 minutes following the center 60, although otherdurations are possible.

The near field view 51 and intermediate field view 52 present ECG datarelative to the center 60 of the far field view 53. The near field view51 provides a pinpoint or short duration view of the ECG data. In oneembodiment, the near field view 51 presents ECG data 55 that beginsabout two seconds prior to and ends about two seconds following thecenter 60, although other durations are possible. The intermediate fieldview 52 provides additional contextual ECG information allowing thephysician to assess the ECG itself and gather a broader view of therhythm before and after a “blow-up” of the specific arrhythmia ofinterest. In one embodiment, the intermediate field view 52 presents ECGdata 56 that begins about 12 seconds prior to and ends about 12 secondsfollowing the center 60, although other durations are possible. Forconvenience, the eight-second interval of the ECG data 56 in theintermediate field view 52 that makes up the ECG data 56 in the nearfield view 51 is visually highlighted, here, with a surrounding box 57.In addition, other views of the ECG data, either in addition to or inlieu of the near field view 51 and the far field view 52 are possible.Optionally, an ECG plot presenting an extended far field view 54 of thebackground information can be included in the diagnostic composite plot50. In one embodiment, the background information is presented asaverage heart rate with day and night periods 58 alternately shadedalong the x-axis. Other types of background information, such asactivity amount, activity intensity, posture, syncope impulse detection,respiratory rate, blood pressure, oxygen saturation (SpO₂), blood carbondioxide level (pCO₂), glucose, lung wetness, and temperature, arepossible.

Examples of the diagnostic composite plot as applied to specific formsof cardiac rhythm disorders will now be discussed. These examples helpto illustrate the distinctive weightings that accompany different formsof rhythm disorders and the R-R interval and ECG waveform deflectioncontext with which they occur. FIG. 7 is a diagram showing, by way ofexample, a diagnostic composite plot 70 for facilitating the diagnosisof sinus rhythm (SR) transitioning into AF. SR is indicated through thepresence of a reasonably steady baseline, but with subsidiary lines ofpremature beats and their compensatory pauses. SR manifests as ashadowing 71 of a high heart rate line and a low heart rate line. AF ischaracterized by irregular heartbeats with a somewhat random variationof R-R intervals, although within a limited range and concentrating in aGaussian-like distribution pattern around a mean that varies over time.Although AF can be diagnosed by viewing a near field view 51 of ECG datashowing heartbeats with reversed P-wave and irregular R-R intervals,this approach may be unclear when viewing “snippets” of ECG data,especially when associated with poor quality ECG signals. The presenceof AF can also be confirmed through a far field view 53 of R-R intervaldata, in which the R-R intervals assume superficially appearingdisorganized, spread-out and decentralized scattered cloud 72 along thex-axis, in comparison to a concentrated, darkened line typical of a moreorganized cardiac rhythm.

FIG. 8 is a diagram showing, by way of example, a diagnostic compositeplot 80 for facilitating the diagnosis of 3:1 atrial flutter (AFL)transitioning into SR with frequent premature ectopic atrial beats. Inthe initial part of the R-R interval plot, the R-R intervals have adiscernible aggregated line in the middle of the cloud 81 when therhythm has yet to stabilize into a set pattern, not quite AF and notquite AFL. Immediately thereafter, a dense line representing firm 3:1atrial flutter stabilizes the rhythm prior to the transition into SRassociated with the presence of two seesawing baselines that result fromfrequent atrial ectopy causing short coupling intervals and thencompensatory long coupling intervals. SR is indicated by the middle ofthe three lines with a low heart rate line consistent with thecompensatory pause (long coupling interval) and a high heart rate linewith the shortest coupling interval representing the series of atrialpremature beats 82, and thus, at a faster heart rate.

FIG. 9 is a diagram showing, by way of example, a diagnostic compositeplot 90 for facilitating the diagnosis of atrial trigeminy. Atrialtrigeminy is characterized by three heartbeat rates appearingintermittently yet reasonably regularly. Although atrial trigeminy canbe diagnosed by viewing a near field view 51 of ECG data, the pattern issignificantly more recognizable in a far field view 53 of R-R intervaldata, in which a repeating pattern of three distinct heartbeat lines arepersistently present and clearly visible 91. This view also provides thephysician with a qualitative feel for the frequency of the eventtroubling the patient that is not discernible from a single ECG strip.

FIG. 10 is a diagram showing, by way of example, a diagnostic compositeplot 100 for facilitating the diagnosis of maximum heart rate in anepisode of AF during exercise. In a far field view 50 of R-R intervaldata, AF manifests through a dispersed cloud of dots (Gaussian-likedistribution) without a discernible main heart rate line representingregular heartbeats 101. Under exercise, the maximum heartbeat can belocated by an increase in heart rate clustered about the cloud 102. Inaddition, individual dots above the 200 bpm range throughout the entire40-minute range indicates the maximum heart rate during exercise. Thevery rapid rise in heart rate can be critical to patient management, assuch bumps in rate by exercise can prove serious and even triggercardiac arrest. Their very presence is easily visualized in the R-Rinterval data plot, thereby allowing the physician to alter therapysufficiently to control such potentially damaging rises in heart rate.

FIG. 11 is a diagram showing, by way of example, a diagnostic compositeplot 110 for facilitating the diagnosis of SR transitioning into AFLtransitioning into AF. In a far field view 53 of R-R interval data, SRmanifests as an uneven main heart rate line with a fluctuating height111. At the onset of AFL, the main heart rate line breaks away at alower heart rate than the SR main heart rate line 112. The episode ofAFL further evolves into AF as characterized by a dispersed cloud ofirregular heartbeats without concentrated heart rate lines 113. Thisview provides critical information to the physician managing AF patientsin that, at a glance, the view provides data that tells the physicianthat the patient's AF may be the consequence of AFL. Such knowledge mayalter both drug and procedure therapies, like catheter ablation detailsof intervention.

FIG. 12 is a diagram showing, by way of example, a diagnostic compositeplot 120 for facilitating the diagnosis of sinus tachycardia andpalpitations that occurred during exercise accompanied by a jump inheart rate. In a far field view 50 of R-R interval data, sinustachycardia is indicated by the presence of a baseline heart rate ofabout 60 bpm 121 that spikes up to around 100 bpm 122 and graduallyslopes down with a wide tail 123, reflecting a sharp rise of heart ratesfollowed by a gradual decline. The associated ECG data in the near fieldand intermediate field views (not shown) can confirm the rhythm as sinusrhythm and a normal response to exercise. This rhythm, althoughsuperficially obvious, was associated with symptoms of palpitations anddemonstrates a sensitivity to heart rate fluctuations, rather than asensitivity to an arrhythmia. This common problem is often dismissed asmerely sinus tachycardia, rather than recognizing the context of achanging rate that generated the patient's complaint, a problem, visibleonly in the R-R interval data plot.

FIG. 13 is a diagram showing, by way of example, a diagnostic compositeplot 90 for facilitating the diagnosis of bradycardia during sleep and aR-R interval pattern characteristic of sleep. Bradycardia refers to aresting heart rate of under 60 bpm. Bradycardia during sleep is oftentempered with occasional spikes of rapid heart rate, which can be asecondary compensatory response to dreaming, snoring or sleep apnea. Ina far field view 50 of R-R interval data, bradycardia manifests as thepresence of a base line heart rate in the range of about 50 bpm 131,coupled with multiple spikes of dots 132 representing intermittentepisodes of elevated heart rate. Such elevations in heart rate during apre-dominantly slower rate may be signs of a cardio-respiratorydisorder. Still other applications of the diagnostic composite plot 80are possible.

The diagnostic composite plots are a tool used by physicians as part ofa continuum of cardiac care provisioning that begins with ECGmonitoring, continues through diagnostic overread and finally, ifmedically appropriate, concludes with cardiac rhythm disorder treatment.Each of these steps involve different physical components thatcollaboratively allow physicians to acquire and visualize R-R intervaland ECG data in a way that accurately depicts heart rate variabilityover time. FIG. 14 is a block diagram showing a system 140 forfacilitating diagnosis of cardiac rhythm disorders with the aid of adigital computer 150 in accordance with one embodiment. Each diagnosticcomposite plot 151 is based on ECG data 166 that has either beenrecorded by a conventional electrocardiograph (not shown) or retrievedor obtained from some other type of ECG monitoring and recording device.Following completion of the ECG monitoring, the ECG data is assembledinto a diagnostic composite plot 151, which can be used by a physicianto diagnosis and, if required, treat a cardiac rhythm disorder, or forother health care or related purposes.

Each diagnostic composite plot 151 is based on ECG data 166 that hasbeen recorded over a period of observation, which can be for just ashort term, such as during a clinic appointment, or over an extendedtime frame of months. ECG recordation and, in some cases, physiologicalmonitoring can be provided through various types of ECG-capablemonitoring ensembles, including a standardized 12-lead ECG setup (notshown), such as used for clinical ECG monitoring, a portable Holter-typeECG recorder for traditional ambulatory ECG monitoring (also not shown),or a wearable ambulatory ECG monitor.

One form of ambulatory ECG monitor 142 particularly suited to monitoringand recording ECG and physiological data employs an electrode patch 143and a removable reusable (or single use) monitor recorder 144, such asdescribed in commonly-assigned U.S. Pat. No. 9,345,414, cited supra. Theelectrode patch 143 and monitor recorder 144 are synergisticallyoptimized to capture electrical signals from the propagation of lowamplitude, relatively low frequency content cardiac action potentials,particularly the P-waves generated during atrial activation. The ECGmonitor 142 sits centrally (in the midline) on the patient's chest alongthe sternum 169 oriented top-to-bottom. The ECG monitor 142 interfacesto a pair of cutaneous electrodes (not shown) on the electrode patch 143that are adhered to the patient's skin along the sternal midline (orimmediately to either side of the sternum 169). The ECG monitor 142 hasa unique narrow “hourglass”-like shape that significantly improves theability of the monitor to be comfortably worn by the patient 141 for anextended period of time and to cutaneously sense cardiac electricsignals, particularly the P-wave (or atrial activity) and, to a lesserextent, the QRS interval signals in the ECG waveforms indicatingventricular activity.

The electrode patch 143 itself is shaped to conform to the contours ofthe patient's chest approximately centered on the sternal midline. Tocounter the dislodgment due to compressional and torsional forces, alayer of non-irritating adhesive, such as hydrocolloid, is provided atleast partially on the underside, or contact, surface of the electrodepatch, but only on the electrode patch's distal and proximal ends. Tocounter dislodgment due to tensile and torsional forces, a strain reliefis defined in the electrode patch's flexible circuit using cutoutspartially extending transversely from each opposite side of the flexiblecircuit and continuing longitudinally towards each other to define in‘S’-shaped pattern. In a further embodiment, the electrode patch 143 ismade from a type of stretchable spunlace fabric. To counter patientbending motions and prevent disadhesion of the electrode patch 143, theoutward-facing aspect of the backing, to which a (non-stretchable)flexible circuit is fixedly attached, stretches at a different rate thanthe backing's skin-facing aspect, where a skin adhesive removablyaffixes the electrode patch 143 to the skin. Each of these componentsare distinctive and allow for comfortable and extended wear, especiallyby women, where breast mobility would otherwise interfere with ECGmonitor use and comfort. Still other forms of ECG monitoring andrecording assembles are possible.

When operated standalone, the monitor recorder 142 senses and recordsthe patient's ECG data 166 and physiological data (not shown) into amemory onboard the monitor recorder 144. The recorded data can bedownloaded using a download station 147, which could be a dedicateddownload station 145 that permits the retrieval of stored ECG data 166and physiological data, if applicable, execution of diagnostics on orprogramming of the monitor recorder 144, or performance of otherfunctions. To facilitate physical connection with the download station145, the monitor recorder 144 has a set of electrical contacts (notshown) that enable the monitor recorder 144 to physically interface to aset of terminals 148. In turn, the download station 145 can be operatedthrough user controls 149 to execute a communications or data downloadprogram 146 (“Download”) or similar program that interacts with themonitor recorder 144 via the physical interface to retrieve the storedECG data 166. The download station 145 could alternatively be a server,personal computer, tablet or handheld computer, smart mobile device, orpurpose-built device designed specific to the task of interfacing with amonitor recorder 144. Still other forms of download station 145 arepossible. In a further embodiment, the ECG data 166 from the monitorrecorder 144 can be offloaded wirelessly.

The ECG data 166 can be retrieved from the download station 145 using acontrol program 157 (“Ctl”) or analogous application executing on apersonal digital computer 156 or other connectable computing device, viaa hard wired link 158, wireless link (not shown), or by physicaltransfer of storage media (not shown). The personal digital computer 156may also execute middleware (not shown) that converts the ECG data 166into a format suitable for use by a third-party post-monitoring analysisprogram. The personal digital computer 156 stores the ECG data 166 alongwith each patient's electronic medical records (EMRs) 165 in the securedatabase 64, as further discussed infra. In a further embodiment, thedownload station 145 is able to directly interface with other devicesover a computer communications network 155, which could be a combinationof local area and wide area networks, including the Internet or anothertelecommunications network, over wired or wireless connections.

A client-server model can be employed for ECG data 166 analysis. In thismodel, a server 62 executes a patient management program 160 (“Mgt”) orsimilar application that accesses the retrieved ECG data 166 and otherinformation in the secure database 164 cataloged with each patient'sEMRs 165. The patients' EMRs can be supplemented with other information(not shown), such as medical history, testing results, and so forth,which can be factored into automated diagnosis and treatment. Thepatient management program 160, or other trusted application, alsomaintains and safeguards the secure database 164 to limit access topatient EMRs 165 to only authorized parties for appropriate medical orother uses, such as mandated by state or federal law, such as under theHealth Insurance Portability and Accountability Act (HIPAA) or per theEuropean Union's Data Protection Directive. Other schemes and safeguardsto protect and maintain the integrity of patient EMRs 165 are possible.

In a further embodiment, the wearable monitor 142 can interoperatewirelessly with other wearable or implantable physiology monitors andactivity sensors 152, such as activity trackers worn on the wrist orbody, and with mobile devices 153, including smart watches andsmartphones. Wearable or implantable physiology monitors and activitysensors 152 encompass a wide range of wirelessly interconnectabledevices that measure or monitor a patient's physiological data, such asheart rate, temperature, blood pressure, respiratory rate, bloodpressure, blood sugar (with or without an appropriate subcutaneousprobe), oxygen saturation, minute ventilation, and so on; physicalstates, such as movement, sleep, footsteps, and the like; andperformance, including calories burned or estimated blood glucose level.Frequently, wearable and implantable physiology monitors and activitysensors 152 are capable of wirelessly interfacing with mobile devices153, particularly smart mobile devices, including so-called“smartphones” and “smart watches,” as well as with personal computersand tablet or handheld computers, to download monitoring data either inreal-time or in batches through an application (“App”) or similarprogram.

Based on the ECG data 166, physicians can rely on the data as medicallycertifiable and are able to directly proceed with diagnosing cardiacrhythm disorders and determining the appropriate course of treatment forthe patient 141, including undertaking further medical interventions asappropriate. The ECG data 166 can be retrieved by a digital computer 150over the network 155. A diagnostic composite plot 151 that includesmultiple temporal points of reference and a plot of R-R interval data isthen constructed based on the ECG data 166, as discussed in detail suprawith reference to FIG. 3, and displayed or, alternatively, printed, foruse by a physician.

In a further embodiment, the server 159 executes a patient diagnosisprogram 161 (“Dx”) or similar application that can evaluate the ECG data166 to form a diagnosis of a cardiac rhythm disorder. The patientdiagnosis program 161 compares and evaluates the ECG data 166 to a setof medical diagnostic criteria 167, from which a diagnostic overread 162(“diagnosis”) is generated. Each diagnostic overread 162 can include oneor more diagnostic findings 168 that can be rated by degree of severity,such as with the automated diagnosis of atrial fibrillation. If at leastone of the diagnostic findings 168 for a patient exceed a thresholdlevel of tolerance, which may be tailored to a specific client, diseaseor medical condition group, or applied to a general patient population,in a still further embodiment, therapeutic treatment (“Therapy”) toaddress diagnosed disorder findings can be generated and, optionally,programmed into a cardiac rhythm therapy delivery device, such as an IMD(not shown), including a pacemaker, implantable cardioverterdefibrillator (ICD), or similar devices.

Diagnosis of cardiac rhythm disorders can also be facilitated viatransformed displays of the cardiac data and an interactive userinterface through which the data displays can be manipulated. Astechnology improves with respect to medical devices and larger amountsof data are able to be collected during a single recording, such as overa period of 7-14 days or longer, displaying the data can becomeproblematic since displays are limited to a size of the screen ormonitor on which the data is displayed. As the amount of data increases,the ability to display all the data at a single time becomes moredifficult. Further, displaying all the data at a single time provides abroad view of the general cardiac rhythm, but not the finer details,such as the individual waves. Accordingly, most cardiac data is providedin finer detail to assist a medical professional in diagnosis; however,the broad or full view can also be extremely helpful to a diagnosingprofessional. For instance, in the broad view, some types of rhythmdisorders can be identified easier than in a detailed view.

Accordingly, the ability to provide a broad or full view, while allowinga user to zoom in and out of the view, in a sliding fashion, permits theuser to view finer details of the broad view sequentially. Further,allowing marking of the cardiac data, such as identifying anddesignating portions of the cardiac data with an event, provide anoverview of a patient's cardiac health. Such transformed data displaysand interactive user interface can be used to select or identifysections of cardiac data for including in the diagnostic composite plot.FIG. 15 is a screenshot of an interactive user interface 180 fordisplaying an overview of an R-R plot. The user interface can bepresented via a web page or software application. For example, a webpage 180 can include tabs 181 a-d provided at a top of the web page 180for directing to other web pages associated with those tabs. The tabscan include tabs for R-R overview 181 a, ECG Trace overview 181 b,Search 181 c, and Report 181 d. The web pages associated with each ofthe Trace 181 b, Search 181 c, and Report 181 d tabs are discussed belowin detail with respect to FIGS. 21, 26, and 27.

The web page 180 associated with the R-R overview tab 181 a can providea patient summary bar 182, an R-R plot 183, a mid-length ECG trace plot184, and a short-length ECG trace plot 192. However, other types of datacan be provided on the web page 180. The patient summary bar 182 caninclude a summary of the patient data including name, birthdate,physician, and age, as well as other types of patient information, achecklist 187 of different types of cardiac events 189, which can becategorized, into groups, such as superventricular arrhythmia andventricular arrhythmia, as further discussed below with respect to FIG.18.

The overview R-R plot data, which can be constructed as described abovewith respect to FIG. 5, can be displayed over a predetermined amount oftime or for the recording lifespan of a monitor that obtains the ECGdata for the R-R plot. In one embodiment, a wearable ambulatory ECGmonitor, as described above with respect to FIG. 14, can record ECG dataover a period of days, such as seven or more days. However, otherrecording times and recording devices are possible.

The mid-length ECG trace 184 and short-length ECG trace 192 can eachinclude a portion of the ECG data that corresponds with a designatedpoint 194 on the R-R overview. The designated point can be indicated viaa marker 194, such as a line or other type of marker. Each of themid-length ECG trace 184 and the short-length ECG trace 192 include apredetermined amount of ECG data prior to and after the point designatedby the marker 194, with the mid-length ECG trace including ECG data overa longer time period than the short-length ECG trace. Any actionsperformed within the relevant portions of the R-R overview can bereflected in the short-length and mid-length views of the ECG trace. Forexample, if a user clicks on a location within the R-R overview, theshort- and mid-length views can change accordingly. Otherwise, if amarker is placed within the R-R overview, the marker can also be placedwithin one or both of the short- and mid-length traces.

The R-R plot data 183 can be linearly arranged along rows beginning on aleft side of the web page to a right side and then continuing left toright on a further row located below the previous row. Each row can benumbered sequentially with the first row representing the earliestrecorded cardiac data and the last row representing the most recentlyrecorded cardiac data. In one embodiment, the R-R plot can be displayedwith markers, such as a bar spanning a length of time, to identify thosesections of the R-R plot that correspond with daytime or nighttime. Forexample, a bar 193 can be positioned under the R-R trace to indicatethose R-R values obtained during a predetermined time, such as at nightor hours when an individual sleeps. Such markers can be helpful sincethe average heartrate decreases during periods of sleep and the markerindicates the reason for the decrease. Other markers can be added to theR-R overview plot, in addition to or in lieu of the daytime/nighttimemarkers, such as markers for each 24 hour period or times during which apatient has previously experienced a cardiac event.

The displayed R-R plot overview 183 can also include one or moreindicators for information related to the cardiac data, such as useridentified cardiac events. Each of the indicators can be displayed as aflag or box, and a letter, number, word, or symbol within the flag orbox can identify a type of indicator being entered. In one example, acircle indicator 191 can be used to identify when a user presses buttonon the ambulatory ECG monitor to indicate a cardiac event, such as whenthe patient experiences a heart flutter, arrhythmia, shortness ofbreath, or any other cardiorespiratory discomfort. Specifically, thecircle indicator 191 can be added to the overview R-R plot 183 toidentify a time at which the cardiac event occurred and to provide apicture of the patient's cardiac data results at the time of the buttonpress. Data identifying the button press can be transmitted wirelesslyupon the press or uploaded from the wearable ambulatory ECG monitorafter recording has terminated.

Additionally, indicators can also be used to identify a time and eventnotated by the patient via an electronic journal entry. For example, apatient can maintain an electronic journal in which cardiac events, suchas a heart flutter, arrhythmia, shortness of breath or any othercardiorespiratory discomfort experienced by the patient, can be entered.For example, a journal entry can be associated with a letter “D”indicator 195. A time at which the journal entry was generated can beused to place the letter “D” indicator in the R-R plot. Alternatively, atime at which the patient identifies that the cardiac event occurred viathe journal entry can be used to place the indicator.

Indicators can also be used to identify noise within the R-R plot or ECGtrace. Prior to display, the cardiac data of the overview R-R plot canbe analyzed to identify noise, such as due to electrode contact,baseline drift, or instrumentation noise, as well as other types ofnoise. A presence of noise in an R-R plot or ECG trace data can lead toincorrect diagnoses. Accordingly, noise can be filtered from the R-Rinterval plot, or identified and marked to indicate noise. The noise canbe identified by a reviewer or automatically via a classifier orartificial intelligence, such as by machine learning or based on one ormore thresholds. The reviewer can be a medical professional or anotherindividual that is trained to read cardiac data. Further, the data canbe reviewed via artificial intelligence to identify noise, as describedin commonly-owned U.S. Patent application, Ser. No. 10/251,576, issuedApr. 9, 2019, which is hereby incorporated by reference in its entirety.The reviewer reviews the data provided in the R-R plot and ECG traces toidentify events of interest that can be provided to a medicalprofessional for use in diagnosing the patient, as further describedbelow.

Once identified, the noise can be removed or can be included in the plotand marked to identify the corresponding data as noise. For example, thedata points associated with noise can be a different color than dataassociated with no noise, can be highlighted, or associated with anindicator, such as a word, number, or symbol to identify the noise.

A physician, nurse, or other medical professional, as well as a trainedcardiac data reviewer can interact with the data of the R-R plot byzooming in and out of particular portions of interest to increase ordecrease a level of detail provided by the plot. For example, the usercan zoom into a portion of the plot to obtain additional data by movinga roller located on a computer mouse, for example. However, othermechanisms for zooming in and out of a display are possible. Thezooming, both in and out, of a particular area of interest in the plotcan be continuous, rather than based on predefined values to ensure thatthe data scale needed is available. Continuous zooming also provides asmoother zooming movement than a zoom action based on predefined zoomlevels.

Since zooming in increases a granularity of the data points in the plotat a location of interest and data points surrounding the location ofinterest, the amount of data in the overview R-R plot may exceed thedimensions of the display screen upon zooming and thus, those datapoints located further from the location of interest may be removed fromthe display. Generally, the zooming in function is similar to increasinga view of an object under a microscope and omitting part of theperipheral views as the view of the object increases in magnification.For a graph, the data points to be removed from the display aregenerally determined based on a distance from the location of interestand the display size, and the removed data points can include those thatare located on all sides of the data points associated with the locationof interest. Accordingly, with respect to the R-R plot, data points forcardiac data occurring immediately prior to or after the data points atthe location of interest can be removed based on the granularity of thedata the location of interest. Thus, the displayed data in the R-R plotcan be discontinuous. Removing such data points can lead to amisdiagnosis since a user is unable to see the data points surroundingthe location of interest, which may represent a cardiac event.

To prevent removal of the data points preceding or following the datapoints that correspond with the location of interest, the zoomingfunction can occur as a sliding action, rather than as a telescopingaction. FIG. 16 is a diagram 300 showing, by way of example, datazooming. Four frames 301-304 each showing a different amount and detailof R-R data are displayed to provide an example of the data zooming. Anoriginal R-R plot 301, such as displayed above in FIG. 15, provides R-Rdata points. As shown in a zoomed out data plot 302, a user zooms out ata point located in the plot 301 represented by a line indicator 305,which is positioned at a location in the plot that includes a buttonpress and a diary entry. The point 305 can be used as a point ofreference during the zooming. Zooming out provides additional datapoints, not included in the original R-R plot, taken over time periods,also not included in the original R-R plot. Conversely, zooming inremoves the data points that were recorded the earliest and the latestto ensure that the displayed data points are continuous after zooming,as displayed in zoomed R-R plots 303 and 304.

For instance, upon receiving instructions to zoom into a portion of theR-R plot, a location of interest on the plot is identified by a user orautomatically using artificial intelligence or a classifier.Subsequently, the data points associated with the location of interestare magnified or the granularity of the data increases. As thegranularity of the data points increases, the display is likely unableto display the same amount of data due to size constraints of thedisplay. To ensure that data located near the data associated with thelocation of interest is maintained and not removed, the data pointsassociated with the earliest recorded data and the latest recorded dataare removed first. For example, the earliest recorded data can belocated in an upper left corner of the plot and can move left along therow until removed from the display, as the granularity of the data atthe location of interest increases. At the same time or a differenttime, the most recently recorded data, which can be located in a lowerright corner of the plot, can slide to the right along the row until outof the size constraints of the display. Accordingly, since the earliestand most recent data is removed first, the data associated with thelocation of interest remains in the display. The more a user zooms intothe R-R data points, the more detail is provided about the data pointsdisplayed. For example, individual data points are more easilyidentifiable in the plot 304 that is more zoomed in.

Within the R-R plot, cardiac events can be identified automatically orvia a reviewer and used to generate a strip of R-R data. In one example,an event can be identified via artificial intelligence, such asdescribed in detail in U.S. Patent Application Publication No.2019/0090769, published Mar. 28, 2019, which is hereby incorporated byreference, and a strip for the event is generated based on R-R dataoccurring prior to, during, and after the event to provide medicalprofessionals with a screenshot of the patient's cardiac data andcondition prior to, during, and after the event occurrence. Each stripof R-R data generated using artificial intelligence can be saved as areport strip with different ECG trace plots. In one example, the reportstrips can include an eight second ECG trace for the near field view, a56 second ECG trace for the intermediate field view, and a 40 minute R-Rplot from the overview R-R plot. However, other time durations arepossible. In one embodiment, each strip can include data recorded overthe same amount of time. Further, each strip of R-R data can beautomatically classified as a particular rhythm type or cardiac eventvia artificial intelligence. The classification of the R-R strip can beassigned to the report strip in which the R-R strip is included. Thedata associated with the saved report strip can be associated with alink to the saved strip within a generated report or in a differentlocation within the user interface.

Additionally, or in lieu of artificial intelligence, the reviewer canmanually identify sections of the R-R plot for use in generating a runof data points of interest. FIG. 17 is a diagram showing, by way ofexample, an interactive user interface 310 for generating a run of data.The user can select a set of R-R data points within the overview R-Rplot that are of interest, such as data reflecting a cardiac event, aswell as data prior to and after the event, to generate the run 311. Inone embodiment, a user can click a mouse, use a verbal command, orutilize a touch screen to identify a location of a cursor within the R-Rplot to mark a beginning 312 and an end of the run 313. For example, auser can left click a mouse and at a beginning 312 of the run and dragthe mouse over the R-R data points until an end 313 of the run when theuser releases the right mouse button. However, other methods forgenerating the run are possible. The run can be highlighted to identifythe data points included in the run. The mid-length ECG trace plot 314stays in sync with the R-R plot, so the run 311 is shown in both panelsand can be adjusted in either panel. For example, adjusting the onsetand offset in the mid-length ECG trace plot 314 can provide more exactpositions based on the more detailed run. Each run can be classified andsaved. FIG. 18 is a diagram showing, by way of example, an interactiveuser interface 320 for displaying a classified run of data. Each run,including the run 311 described above with respect to FIG. 17 can beassigned an identifier, such as a number, name, or symbol 191 toidentify the run. Additionally or in lieu of the identifier, the run 311can include highlighting or a bar that runs along the data points in therun, such as above or below, to identify the run. Such identifiers canalso be placed in the short and mid-view ECG trace plots. Further, thebar or highlighting representing the run 311 can be one color, while thebar or highlighting representing an automatically determined strip ofR-R data points can be a different color.

Once generated, each run can be annotated with a rhythm type representedby the cardiac data in that run. For example, the run 311 of R-Rinterval data represents AF 321 by a dispersed cloud of dots(Gaussian-like distribution) without a discernible main heart rate linerepresenting regular heartbeats, as described above in detail withrespect to FIG. 10. The AF classification 321 can be assigned by areviewer or automatically determined, and is assigned to the run andnoted in the overview R-R plot by assigning a marker for AF to the run.Other rhythm types used to classify the strips can include AtrialFibrillation, Atrial Flutter, Atrial Tachycardia, Atrioventricular NodalReentry Tachycardia, Atrioventricular Reentrant Tachycardia, SVAberration, Idioventricular Rhythm, Sinus Bradycardia, Sinoatrial node,Premature Atrial Contraction, Sinus Exit Block, Junctional, AV Block,and Longest Pause. However, other types of cardiac rhythms and rhythmmeasurements are possible for classifying the report strips.Additionally, the runs that are saved to a database can be associatedwith a saved symbol 322 to indicate that the run has been saved. Thecardiac data associated with saved runs can be analyzed to provide asummary of cardiac measurements, as described in detail below withrespect to FIG. 19. Further, the data of each saved run can include alink directly to the saved run located in a report or a differentlocation of the user interface.

In a further embodiment, runs that are automatically determined via aclassifier or artificial intelligence can be reviewed by users andedited. Any edits to a run can be provided as feedback for improvingalgorithms executed by the classifier or artificial intelligence. Thesystem can also keep track of manually marked runs to use for improvingthe automatic algorithms. Further, all edits can be tracked andmaintained, including information such as who made the edit, when theedit was made, and information the edit included.

Other cardiac rhythm types can be classified in additional runs. Forexample, FIG. 19 is a diagram showing, by way of example, an interactiveuser interface 330 generating a further run of data points. The run 331occurs after the AF run described above with respect to FIG. 18 and isdefined by a beginning 332 and an end 333 of the run. To manuallyclassify and save the run 333, a user can select the correct rhythm typefrom a list of rhythm types 335 in the patient summary bar 337 andselect a save button. However, the run can also be classifiedautomatically and in one embodiment can be reviewed and possibly revisedby the user. Once the run has been classified and saved, a number ofoccurrences 338 for the classified rhythm type, here AFL, can beincreased by one occurrence. The number of occurrences 338 can bedisplayed in the patient summary bar and associated with the rhythmtype.

Upon generating a run of data points, a set of cardiac rhythmmeasurements can be automatically calculated based on the cardiac datapoints that fall within the start and end points of the run. The cardiacrhythm measurements can include a length of the run, offset, number ofepisodes of the event identified in the run, the burden, longestepisode, average heart beats per minute (bpm), minimum bpm, and maximumbpm. However, other cardiac rhythm measurements are possible, such asfastest heart rate and longest duration heart rate. One or more of thecardiac measurements can be displayed in a pop up notification 336adjacent to the run, while one or more of the measurements can bedisplayed in the patient summary bar 337, such as under the classifiedrhythm type 335. In one embodiment, the measurements can be based on a30 second window of data points in the run. Alternatively, each 30second segment in the run is calculated to find the specificmeasurements. Other methods for computing a fastest or maximum heartrate are possible, such as finding the maximum average heart rate ascomputed over 30-second windows across the data set. The 30-secondaverage is useful for a general average heart rate. Another computationmethod is finding the maximum heart rate as computed over 3-beat windowsacross the data set. The 3-beat average is useful for finding thefastest region of tachycardia runs. The “windows” across the data setare incremented such that they overlap, such as to find the actual maxanywhere in the data, rather than sequentially aligned next to eachother, which would give a false answer since the max would depend onwhere the next sequence starts/stop.

Subsequently, the run 331 can be classified as described with respect toFIG. 20, which provides a diagram showing, by way of example, aninteractive user interface 340 for assigning a classification to thefurther run of FIG. 19. For example, the run includes a dense line ofR-R data points representing firm 3:1 atrial flutter, as described abovewith respect to FIG. 8, and is assigned a classification of atrialflutter 341.

After classification, the runs associated with each rhythm type can becalculated and stored. The cardiac rhythm measurements can be determinedacross all the runs and automatically generated data strips obtainedfrom the overview R-R plot to provide a summary of the events ofinterest and cardiac rhythms. The report strips and associated rhythmcardiac factors can be collected and provided in a diagnostic report forthe patient, as further described below with respect to FIGS. 18 and 19.

The cardiac rhythm classifications and cardiac rhythm measurements canbe displayed in the patient summary bar 342, which provides summary databased on the cardiac rhythm factors determined from the runs and datastrips. Specifically, the patient summary offers a medical professionalor reviewer, such as an ECG technician with a quick overview of rhythmsexperienced by the patient during the recording period. The patientsummary bar 342 can include patient identification information,including patient name or identification number, and date of birth.Other types of patient identification information are possible. Thepatient summary bar can also include a checklist 343 of cardiac rhythmpatterns, which can be categorized as cardiac summary, supraventricular,impulse, ventricular, device, and other. Each category 344 can beassociated with one or more cardiac rhythm types 345. For example, acardiac summary category can be associated with normal sinus rhythm,bifid P-wave, ectopic atrial rhythm, and pre-excitation, while a supraventricular category can be associated with atrial fibrillation, atrialflutter, atrial tachycardia, atrioventricular nodal reentry tachycardia,atrioventricular reentrant tachycardia, and SV aberration. Othercategories and associated rhythm types are possible. Each rhythm type345 can be displayed under the appropriate category 344 with a number ofoccurrences of that rhythm experienced by the patient. Listing each typeof cardiac rhythm can help ensure a medical professional or reviewerthat the rhythm was considered, but not identified within the overviewR-R plot.

Each category can be associated with a number of runs or data strips foreach rhythm type for that category. For example, there are 6 events ofsupraventricular rhythms, including 4 instances of atrial fibrillationand 2 events of atrial flutter. Upon selection of one of the rhythmtypes 345 in the patient summary bar 342, such as atrial fibrillation,further information can be displayed, including a number of strips withthat rhythm type, a number of episodes of that rhythm type, a durationof the longest episode, minimum heart rate, maximum heart rate, andaverage heart rate. Other types of information are possible. Further,the number of runs and strips, as well as button presses and diaryentries can be totaled and displayed via a field box 346 for quickreview.

Returning to FIG. 15, the web page 180 can also include an overview ECGtrace Users, such as medical professionals or reviewers can accessdifferent views of the cardiac data recorded by the wearable ambulatoryECG monitor to facilitate diagnosis of the patient. FIG. 21 is ascreenshot of an interactive user interface 350 for displaying anoverview ECG trace plot 201. The interactive user interface can beimplemented via a web page or software application. The web page 350 caninclude tabs 351 a-d for an overview R-R plot web page 351 a, trace plot351 b, search 351 c, and report 351 d. The web page 350 associated withthe trace plot tab 351 b can include an overview ECG trace plot 352, aportion of the ECG trace plot 354, an R-R plot 353 representing aportion of the overview ECG trace plot, and a patient summary bar 355.

The overview ECG trace plot 352 can include ECG data recorded for apredetermined amount of time or recorded over the life of the wearableambulatory ECG monitor. As described above with respect to the R-R datapoints of FIG. 15, the ECG trace can be displayed along horizontal rowsthat continuously wrap from left to right and top to bottom to fill thedisplay. The earliest recorded data can be provided in a top left cornerand the most recently recorded data can be located in a bottom rightcorner of the display. However, other displays of the data are possible.

Users can zoom in and out of the trace data to obtain further detail.FIG. 22 is a diagram showing, by way of example, data zooming 360 of theECG trace plot of FIG. 21. The diagram includes six different views361-366 of the ECG trace plot at different stages of zoom. A first viewof the ECG trace plot corresponds to the ECG trace plot as describedabove with respect to FIG. 21 with a point of focus 367, at whichzooming into the data will occur. The point of focus 367 can bedisplayed via a line, dot, circle, or other marker. Upon zooming intothe ECG trace, data that was collected at a beginning of recording andmost recently is removed from the display 362 to provide further detailwith respect to the ECG trace remaining in the display. Further, asadditional zooming occurs at the point of focus 367, further detail isprovided about the information closest to the point of interest 367, asdisplayed 363-366.

A reviewer can interact with the displayed ECG trace data. FIG. 23 is adiagram showing, by way of example, an interactive user interface 370for displaying a selected data strip 372. The interface 370 displays anoverview ECG trace 371, a portion of the R-R trace 375 that correspondswith the displayed ECG trace 371, a short-view ECG trace 376, and apatient summary bar 377. The data displayed via the short-view ECG canbe selected based on an identified cardiac event in the overview ECGtrace, as described below.

Each of the short-view ECG 376, R-R plot 375, and overview ECG trace 371can be manipulated by a user, such as a medical data reviewer oranalyzed automatically to obtain data for presenting to a medicalprofessional for diagnosis. As described above, segments of the cardiacdata can be selected manually as runs or automatically as data strips toobtain data about cardiac events experienced by the patient. In oneembodiment, the manually selected runs can each include data collectedover different lengths of time, while the automatic data strips eachinclude data collected over a predetermined amount of time. Theautomatic data strips can be recognized via artificial intelligencebased on an identified cardiac event. Each automatic data strip can berecognized via a data marker 372, such as a line or bar, which canidentify a range of data included in that strip. In one example, as thestrip can cover an eight second duration of time; however, otherdurations are possible as identified automatically or via a user. Forinstance, the marker 372 can include upper and lower bounds to indicatea duration of time which is associated with a portion of the overviewECG trace plot 371. In one example, a cardiac event identified by theartificial intelligence can be identified as a center 374 of the datastrip and a predetermined duration of time prior to and after the centerof the identified center is determined for inclusion in the strip. Eachstrip can be assigned a rhythm classification 378 and an identifier 374.

Users can navigate between the short-view ECG trace 376, the R-R plot375, and the overview ECG trace plot 371. For example, a user can selecta point within the R-R plot 375, such as via a cursor, and the sameposition can be identified in the overview ECG trace plot 371.Additionally, users can select a point within the overview ECG traceplot and the same position can be identified in the R-R plot.

Runs of cardiac data can also be generated manually by a reviewer orother user via the overview ECG trace. FIG. 24 is a diagram showing, byway of example, an interactive user interface 390 for generating a runof ECG trace data 391. The user interface 390 can include a patientsummary bar 395, a short-view ECG trace 398, an R-R plot 396, and anoverview ECG trace 391. Within the overview ECG trace 391, a user canplace markers at a beginning 393 and an end 394 of a strip of data togenerate a run 392, as described above in detail with respect to FIG.17. Each run can include an indicator, such as highlighting or a bar tospan a length of the run. Further, the run can be generated anywherewithin the overview ECG trace 391, including within a data stripidentified via artificial intelligence 397.

Once generated, the run can be classified and saved. FIG. 25 is adiagram showing, by way of example, an interactive user interface 400for saving a run of ECG trace data. The user interface 400 can include apatient summary bar 401, a detailed data segment 403, which provideinformation about a run of data or a data strip, a short-view ECG trace,a portion of an R-R plot 404, and an overview ECG trace 409. The ECGtrace 409 includes markers for a data strip 406 and a run 405. The run,as generated and described above with respect to FIG. 24, can be savedvia a user, such as by a “save button” (not shown), and classified witha rhythm type, such as Atrial Tachycardia. The status of the run and theclassified rhythm type can be displayed in the detailed data segment403. Also, the run 405 can be identified via a bar that spans a distanceof the run.

Once the runs and data strips are classified and saved by rhythm type, auser can select one or more of the categories 407 of rhythm types orindividual rhythm types 408 in the patient summary bar 401 by selectinga particular category 407 or rhythm type 408. Upon selection of thecategory or rhythm type, all the data strips or runs classified as thatcategory or rhythm type can be highlighted within either the overviewR-R plot or overview ECG trace, and displayed. FIG. 26 is a diagram ofan interactive user interface 420 for conducting a search for cardiacevents. The interface, such as implemented via a web page 420 caninclude tabs 421 a-d for an overview R-R plot web page 421 a, trace plot421 b, cardiac event search 421 c, and report 421 d. The web page 420associated with the search tab 421 c can include rhythm search results422, a partial trace ECG 423, a partial R-R plot 424, and a patientsummary bar 425. A user can enter a search query by selecting one ormore of the categories or rhythm types within the patient summary bar425 to identify those runs or data strips that satisfy the selectedcategory or rhythm type. Additionally, a user can enter a search valuefor minimum or maximum heart rate, average heart rate, or contiguousbeats or other search fields provided in the patient summary bar.

Results of the search include runs or data strips that satisfy the queryand can be displayed in the results section 422. Further, a selectedresult is displayed via the partial trace ECG 423 and within the R-Rplot 424. Specifically, as you select a rhythm strip from the searchresults, the corresponding area in the partial trace ECG and R-R plotscan be highlighted or if necessary, the partial trace ECG and R-R plotcan be updated to include the selected rhythm strip.

The search tool could be provided as a separate tab, as described above,or integrated into the other tabs. In all views, a list of searchresults strips are identified and the run associated with the searchfinding is highlighted. For example, if a search found a run of 12 beatsof Ventricular Tachycardia, clicking on that search strip would show therun in the partial trace ECG and R-R plot, and the 12 beat region wouldbe highlighted with a run that can be saved.

One or more of the runs or data strips can be identified and selectedfor use in a report for the patient. The report can be used by a medicalprofessional to diagnose a cardiac condition of the patient. FIG. 27 isa diagram of an interactive user interface 440 for displaying data forinclusion in a patient report. The interactive interface can beimplemented via a web page 240, which can include tabs 441 a-d for anoverview R-R plot web page 441 a, trace plot 441 b, search 441 c, andreport 441 d. The web page 440 associated with the report tab 441 d caninclude a rhythm summary bar 447 for the patient and one or more reportstrips 442 for including in a patient report to be provided to aphysician or other medical professional for use in diagnosis of apatient. Each report strip 442 can include a diagnostic composite plotas described above in detail with respect to FIG. 6 based on a manuallygenerated run or the automatically generated data strip as the far fieldview 444 with corresponding R-R interval data plots 445 and near-fieldviews 446. The displayed report strips can include only a select set ofreport strips, such as those associated with runs or data stripsexhibiting a particular cardiac rhythm or all the report stripsgenerated for the patient based on the cardiac data obtained from thewearable ambulatory ECG monitor for that patient. For example, onlythose runs or data strips that are of particular significance can beselected for providing to a user, while the other runs or data stripscan be brought to the medical professional's attention as a group, forinstance as a number of each rhythm occurrence.

The rhythm summary bar 441 can include patient identificationinformation and a checklist of cardiac rhythm patterns, which can beorganized by category of pattern type and can include the same ordifferent rhythm categories as the rhythm categories in the checklist ofthe overview 441 a and trace 441 b tabs. Additionally, the rhythmsummary information is determined based on the report strips 442selected for inclusion in the patient report.

The report strips, along with the patient summary information, can beexported to generate a formal report provided to a medical professionalfor diagnosis and for inclusion in the patient's medical file. FIG. 28is a view of a patient report 460. The patient report 460 can includepatient identification information 461, a checklist of rhythm types 462,a heart rate summary 263, an overview R-R plot 464, and record strips465. The patient identification information 461, such as name,identification number, date of birth, sex, type of cardiac monitor,physician, physician contact information, monitor application location,monitor identification number, monitor recordation duration, and monitorrecording start and end dates. Other types of information are possible.A checklist of rhythm types 462 can also be included in the report 460.

The rhythm types can be the same or different than the rhythm typesassociated with the web pages for the overview and trace tabs R-R plotand ECG trace. Each of the rhythm types can be colored or highlightedbased on a presence of that rhythm type in the cardiac data obtainedfrom the wearable ambulatory ECG monitor. For example, rhythm types withblack font indicate a presence of those rhythms in the cardiac data andthe rhythms in gray font indicate that those rhythm types are notpresent in the cardiac data. Highlighting the rhythm types present inthe cardiac data, while deemphasizing non-present rhythm types providesa quick view for the medical professional regarding cardiac eventsexperienced by the patient. The checklist 462 can remain consistentacross all patient reports, which allows the major findings of thecardiac data to include only the most important major findings since thechecklist of rhythm types and heart rate summary give comprehensiveresults and allows each physician to focus on the area of the reportbelieved to be most interesting.

The heart rate summary 463 can provide an average heart rate, as well asadditional information, including a portion of an ECG trace. Theoverview R-R plot 464 can include R-R data points from cardiac dataobtained over the recordation period of the ambulatory ECG monitor. Manyrhythms often present in repeatable patterns and the overview R-R plotprovides an overview of the frequency, duration, and time of day ofvarious rhythms over the recording duration. The plot can be annotatedwith patient button presses, diary entries, and report strips, asdescribed above. The annotations for the report strips can each act as alink to the corresponding report strip.

The report strips 465 generated for a patient from cardiac data recordedby the ambulatory ECG monitor can also be included in the report. Eachreport strip 465 can be annotated with an event or rhythm type. Forexample, if the patient has a diary entry for “lightheadedness,” thedata recorded during the time the patient experienced lightheadednesscan be labeled “lightheadedness.” Additionally, a portion of the cardiacdata that resembles premature atrial contractions can be labeled PAC.FIGS. 29-31 are diagrams showing, the report of FIG. 28 in furtherdetail.

Once generated, the report can be forwarded to a medical professionalfor review, analysis, and diagnosis of the patient's condition.Additionally, the report can be stored in a patient's electronic orpaper medical file for later reference.

Interactions with the cardiac data are described above with respect to amouse and a cursor; however, a user can also interact with the datausing voice commands or multi-touch gestures on touch-enabled displays,which can greatly improve the communication interface between humans andmachines. For example, in a log segment of information, a user wants tomark premature ventricular contraction events, which can occur byholding one finger on a PVC paint bucket provided in an interface andtouching each PVC event in a waveform or ECG trace display. Other typesof events can be marked the same way. Other touch gestures can includepinching portions of the interface to zoom in and out with time, twofinger scrolling for changing an amplitude of a signal displayed, andone finger scrolling for moving a waveform up and down, and left andright. Double taps could bring up contextual menus, while tapping anonset or offset of a rhythm of interest with the right hand, whileplacing the left hand on a menu item of interest, or vice versa, allowsa user to classify report strips or process portions of the R-R plot orECG trace. Calipers, such as accessed via the paint box, can be used forbasic interval measurements following size and rate expansion for quickPR, QRS, and QT measurements. Also, verbal commands can be added to handcommands for ease of use. Other types of gestures are possible.

In a further embodiment, physiological data collected via physiologicalsensors within or associated with the cardiac device can be displayedwith the cardiac data. Further, sections of the physiological data canbe selected based on abnormal results, rhythms, or measurements tocreate and store strips or runs. Such physiological sensors can collectphysiological data, including heart rate, temperature, blood pressure,respiratory rate, blood pressure, blood sugar, oxygen saturation, minuteventilation, and so on; as well as physical states, such as movement,sleep, footsteps, and the like; and performance, including caloriesburned or estimated blood glucose level. Other types of physiologicaldata are possible. When an abnormal measurement or data is identifiedfrom the physiological data, a time when that data was collected can beidentified on the R-R plot or the ECG trace. For example, the oxygenrate of a patient can be identified as low and a time when the oxygenmeasurement was obtained can be determined. An indicator of the oxygenmeasurement can be placed within the R-R plot or ECG trace at thecorresponding time to allow a medical professional to view the cardiacdata that occurred when the patient's oxygen level was low.

Further, data regarding body position and posture can be obtained foruse with the cardiac data. For example, a position of a patient can bedetermined continuously, when a change in position is detected,periodically, or randomly. The positions can include supine, prone,upright, standing, and kneeling, as well as other types of positions.Use of the body position or posture can be helpful to identifyunexpected changes in a patient's cardiac data. For instance, a patientis asleep during the night and a sudden increase in heart rate isidentified. The increase could be due to a cardiac event, especially ifthe patient is still asleep and not performing any activity.Alternatively, if the patient's position is now upright, the increasecould be due to the patient getting up and out of bed, and may be anormal heart rate for such activity.

The collected and displayed cardiac and physiological data can beobtained via a dermal cardiac device, such as described in detail incommonly-owned U.S. Pat. No. 9,433,367, issued Sep. 6, 2016, and incommonly-owned U.S. Patent Application Publication No. 2017/0258358,published Sep. 14, 2017, or via an implantable cardiac device, asdescribed in further detail in commonly-owned U.S. Patent applicationPublication No. 2019/0167139, published Jun. 6, 2019, which are herebyincorporated by reference in their entirety.

While the invention has been particularly shown and described asreferenced to the embodiments thereof, those skilled in the art willunderstand that the foregoing and other changes in form and detail maybe made therein without departing from the spirit and scope.

What is claimed is:
 1. A system for facilitating a cardiac rhythmdisorder diagnosis with the aid of a digital computer, comprising: anelectrocardiogram (ECG) monitoring and recording device; a downloadstation adapted to retrieve cutaneous action potentials of a patientrecorded over a set period of time by the ECG monitoring and recordingdevice as ECG data; and a processor and memory within which code forexecution by the processor is stored, wherein the processor: accesses anR-R interval plot of the ECG data comprising R-R intervals plotted alongan x-axis of the plot and heart rates associated with the R-R intervalsplotted along a y-axis of the plot, wherein the R-R intervals arecalculated as a difference between recording times of successive pairsof R-wave peaks and each heart rate is associated with each timedifference; identifies a plurality of runs of the R-R intervals in theplot, each run comprising start and end markers and a pattern of the R-Rintervals representing a cardiac event; automatically calculates cardiacrhythm measurements based on predetermined time windows defined withineach run; tracks occurrences of different types of cardiac events byincreasing a count of occurrences for one type of cardiac eventconsistent with the cardiac event represented in each of the runs; andreports one or more of the cardiac events and the cardiac rhythmmeasurements.
 2. A system according to claim 1, wherein the runs areeach determined automatically or manually by a reviewer.
 3. A systemaccording to claim 1, wherein the predetermined time windows areoverlapping.
 4. A system according to claim 1, wherein the processorassigns a marker representing the cardiac event represented by each run.5. A system according to claim 1, wherein the processor assigns a markerto at least one location within the plot to represent a button press ofthe ECG monitoring and recording device by a wearer, wherein the buttonpress indicates a cardiac event.
 6. A system according to claim 5,wherein the processor generates a run based on the button press of theECG monitoring and recording device by the wearer.
 7. A system accordingto claim 1, wherein each cardiac event represented by a run isdetermined automatically or manually by a reviewer.
 8. A systemaccording to claim 1, wherein the plot is displayed adjacent to apatient summary bar and the patient summary bar displays a checklist ofcardiac rhythm patterns and each cardiac rhythm pattern is associatedwith a list of cardiac event types.
 9. A system according to claim 1,wherein the processor provides at least one marker within the plotrepresenting one of daytime, nighttime, a 24 hour period, or aparticular time of day during which a wearer of the ECG monitoring andrecording device has previously experienced a cardiac event.
 10. Asystem according to claim 1, wherein the processor highlights the runsor underlines the R-R intervals within the runs.
 11. A system forfacilitating a cardiac rhythm disorder diagnosis with the aid of adigital computer, comprising: an electrocardiogram (ECG) monitoring andrecording device; a download station adapted to retrieve cutaneousaction potentials of a patient recorded over a set period of time by theECG monitoring and recording device as ECG data; and a processor andmemory within which code for execution by the processor is stored,wherein the processor: accesses an R-R interval plot of the ECG datacomprising R-R intervals plotted along an x-axis of the plot and heartrates associated with the R-R intervals plotted along a y-axis of theplot, wherein the R-R intervals are calculated as a difference betweenrecording times of successive pairs of R-wave peaks and each heart rateis associated with each time difference; identifies a plurality of runsof the R-R intervals in the plot, each run comprising start and endmarkers and a pattern of the R-R intervals representing a cardiac event;automatically calculates cardiac rhythm measurements based onpredetermined time windows defined within each run; displays one or moreof the cardiac measurements in a pop-up notification adjacent to the runor one or more of the measurements in a patient summary bar adjacent tothe R-R interval plot; tracks occurrences of different types of cardiacevents by increasing a count of occurrences for one type of cardiacevent consistent with the cardiac event represented in each run; anddisplays the occurrences of the difference cardiac events via thepatient summary bar.
 12. A system according to claim 11, wherein theruns are each determined automatically or manually by a reviewer.
 13. Asystem according to claim 11, wherein the predetermined time windows areoverlapping.
 14. A system according to claim 11, wherein the processorassigns a marker representing the cardiac event represented by each run.15. A system according to claim 11, wherein the processor assigns amarker to at least one location within the plot to represent a buttonpress of the ECG monitoring and recording device by a wearer, whereinthe button press indicates a cardiac event.
 16. A system according toclaim 15, wherein the processor generates a run based on the buttonpress of the ECG monitoring and recording device by the wearer.
 17. Asystem according to claim 11, wherein each cardiac event represented bya run is determined automatically or manually by a reviewer.
 18. Asystem according to claim 11, wherein the patient summary bar displays achecklist of cardiac rhythm patterns and each cardiac rhythm pattern isassociated with a list of cardiac event types.
 19. A system according toclaim 11, wherein the processor provides at least one marker within theplot representing one of daytime, nighttime, a 24 hour period, or aparticular time of day during which a wearer of the ECG monitoring andrecording device has previously experienced a cardiac event.
 20. Asystem according to claim 11, wherein the processor highlights the runsor underlines the R-R intervals within the runs.